EXCITATION OF A HIGHER-ORDER TRANSVERSE-MODE IN AN OPTICALLY PUMPED IN0.15GA0.85N IN0.05GA0.95N MULTIQUANTUM-WELL LASER STRUCTURE/

We report a comparison between measured and calculated far field data for an optically pumped In0.15Ca0.85N/In0.05Ga0.95N multiquantum well laser structure with AlGaN cladding layers. Optical pumping of the sem iconductor device was performed with a pulsed 337 nm N-2 laser, whose beam was focused to a narrow stripe. A thin upper cladding layer allow ed efficient pumping of the In0.15Ga0.85N/In0.05Ga0.95N laser structur e. Despite high distributed cavity losses of at least 30 cm(-1), and a lthough gain occurred in the small active region only, the seventh ord er transverse mode was supported in a waveguide formed by the entire 5 -mu m-thick epitaxial layer structure. Excellent agreement is demonstr ated between measured and calculated far field patterns of the lasing mode. (C) 1997 American Institute of Physics.